Joseph louis boutin



J. L. ROUTIN.

APPARATUS FOR REGULATING THE FIRING 0F euws.

APPLICATION FILED SEPT. 7, I9l7.

- Patented J uly'fi, 1920.

2 SHEEIS-SHEEI I.

fizz enter.

. J..L. ROUTIN. 1

APPARATUS FOR REGULATING THE FIRING 0F GUNS.

APPLICATION HLED SEPT. 7, 1917.

- Patented July 6, 1920.

2 SHEETS-SHEET PATENT OFFICE.

JOSEPH LOUIS ROUTIN, OF PARIS, FRANCE.

APPARATUS FOR REGULATING- THE FIRING OF GUNS.

Application filed September '7, 1917.

To all whom it may concern:

Be it known that I, JOSEPH LoUIs RoU'rIN,

a citizen of the French Republic, and a resi dent of 2- Rue Olchanski, Paris, France, have invented a new and useful Improvement in Apparatus for Regulating the Firing of Guns, which invention is fully set forth in the following specification.

The present invention relates to improvements in tachometrical apparatus such as described in my application for U. S. Patent Sr. No. 182,311, filed July 23, 1917, now Patent No. 1,345,697, dated July 6, 1920, and has for its object to provide apparatus for the determination of corrections in lateral aim 5 and in vertical aim a while taking into consideration a corrected time of flight due to the shape of the trajectory.

The correction for lateral aim will be.

D2O do: ama).

and the correction for the vertical aim will t D doc) D D dt 0 t denoting the duration of the projectiles transit, D the distance at the time tzO when the readings are made, D the distance at the time tzt, when the shot is fired, D the distance at the time t:t,lt when the projectile reaches the object.

n -n 30 do) 6 V'O'TS 0., DTX n a). D12 D11 D20 do: Voos 0 D D d? 0 The quantity D ,D m T Specification of Letters Patent.

Patented July 6, 1920.

Serial No. 190,160. I

the time of flight of the projectile. When the angular corrections 8 and c are small, the above formulae may be written- D do:

1p); a? o D2 Qe ]),1), dt 0 z D11 V cos 6 is a linear time function and is called the time of flight and would be the correct time of flight in case the projectile would travel with a constant speed, or, in other words, it would be the time of flight if the trajectory were a straight or substantially straight line. This quantity is represented by t Due to the change in speed of the projectile in passing along the trajectory, it is necessary to determine a new or corrected time of flight for correcting the directional coordinates of the sighting device. Let this time be called It is evident that this quantity depends upon the shape of the trajectory and is only accurately determined when D D V cos 0.,

is substantially a lineal time function. From the original formula the theoretical method of determining 6 from 25 is illustrated in Fig. 1 and its practical application is illustrated in Figs. 3 and 4.

WVithout being strictly exact, these formulae nevertheless give very near results. They have, besides, the great advantage of allowing a mechanical determination of the term D DIDZ which represents the duration of transit by which the angular speeds read at the time t O must be multiplied in order to obtain the correction to be made in the aim. This result is obtained by means of the following geometrical construction.

Referring to Fig. 1, A, B, C is the graph which gives the distances of the aerial target in functions of time. C is the point on the curve corresponding to the value i=0 and D=D D and extrapolated distance after the time of flight t D an extrapolated distance after the fictitious time of flight t B is the angle which the tangent to the curve at C makes with the vertical through C.

From tables of firing may be obtained, for each angle of sight, the time t in which it takes the projectile to reach a distance d. For every value of t above a value t one may place (Z=F (t, a and, as in practice the variations of the angle of sight have only a small influence on the values of (i,

one may assume that the values of d are given with a close approximation by the function Z=F (2 a Let this curve be traced in a, b, 0.

Join a to 0. Draw a vertical through C meeting a, c in r. Draw a vertical through c and pass a horizontal line through 1 meeting the vertical through c in point 8. Connect a and s. Designate by g and h the points of meeting of the vertical through C with as on the one hand and with the horizontal of the point a, on the other hand. By construction,

D h or t =se 9 2 D1 For 86 substitute its equivalent O t Then D2 25 =t- 2 ZDjJ)2 Fig. 1 also illustrates a chronotachometer,

shown and described in my application Sr. No. 182,981, filed July 26, 1917, whereby, when 25 is known, the coeflicients of proportionality of the chronotachometer can be regulated without having to read 25 The example is given under the assumption that it is required to determine 5.

In Fig. 1, L L indicates a sighting device mounted on a vertical shaft Q, P, which is adapted to be turned by a handle M through worm-gear connections. The angular movements of the sighting device are imparted to tachometric means, such as a direct current magneto N, in the circuit of which is a resistance P, Q, and a voltmeter V. It will be noted that the readings of the voltmeter V depend on the speed or voltage developed by magneto N and the position of the con tact R along the resistance P, Q. For

brevity, let R, be the resistance of R, Q and R the resistance of P, Q; V the difference of potential between the magneto terminals, and G the difierence of potential between the point R and the terminal of the mag neto, then or G for example, and R varies as vR, R

1 D20 (Zoo G r R X w n, 71?),

By selecting proper graduations, the voltmeter may be made to read directly hence,

is read direct in the voltmeter V In Figs. 3 and 4: is shown a chronotelemetrical apparatus, such as described and claimed in my U. S. application Serial No. 182,311, provided with my present improvement for determining the fictitious time of flight t So much of the chronotelemetrical apparatus will here be described as is necessary to show the connection of the present improvement therewith. Referring to Figs. 3 and 4:, a drum 8 is driven at a uniform speed by any suitable means such as a shaft operated by a handle 7 and controlled by clockwork 9. Drum 8 advances a sheet of paper 10, 11, 12, 13 under a tracing point mounted on a carriage 14 having below a nut which is mounted on a screw 15. This screw 15 is rotated by aid of range-finding mechanism, not shown, connected through gearing. The position of the carriage on the screw 15 is determined by a cord connection 17 with the range-finder. Under the combined movements of the paper and the tracing point, a curve A, B, C is produced, the horizontal ordinates of which represent ranges of the target at any moment of time t Mounted on the carriage 14: is a revoluble pointer 22 adapted to give the direction of the tangent to the curve A, B, C at the point C. Located above the traveling sheet of paper is a stationary plate 23, 24, 25, 26 onwhich is engraved one or more curves a, b, 0 which are located above C at a distance 25 and which give the distances of the projectile for different values of the angle of sight. A square or straight edge 27 slides along the rod 28 and permits of directly reading the fuse-setting distance or distance debouchoir D on the graduated drum 29 of Fig. 4 or cylinder X, Y of Fig. 1 in the vertical which passes through c. The graduations placed on the drum are the distances debouchoir, that is distances in kilometers for setting the fuse-firing device. This distance is a function of the actual distance and of the sight.

The drum is therefore provided with different graduations corresponding to different angles of sight.

To properly position the drum, an indexbutton 30 is provided for turning cylinder 29. This cylinder may also permit the windages to be directly read off.

The duration of the fictitious or corrected time of flight 25 is read on a graduated rule 31 mounted on the carriage 14. This rule can be displaced in a manner to bring one or the other of its stops to the vertical through C, thus always permitting point 0 to be visible.

The graphic construction which permits the fictitious flight to be determined is obtained by the aid of two elastic strings 2 and 33, such as two steel wires, fixed on the one hand to the point a and on the other hand to carriages 34 and 35 which can be displaced along a threaded rod 36. As the angle between the two elastic cords 34 and 35 varies only very slightly with the times, and the fact that the carriage 35 is mounted on carriage 34, the manipulation necessary for determining is reduced to displacing 34 in a way that '32 passes through 0. In order to determine times for other angles between the two cords 32 and 33, the square 27 is used which is placed on the vertical line passing though point e.

The intervals of firing are regulated by aid of a gong 44 actuated automatically every t, seconds.

What I claim is 1. In combination with telechronographic means for predicting the distance of an aerial target and the time of flight of a projectile, means for proportioning times to distances in accordance with said predicted time and distance of said target and an index element movable with said first-named means for indicating the co-eflicient of proportionately 2( 0) D D by which the angular speed must be multiplied.

2. In apparatus as claimed in claim ,1 the combination of electromagnetic means responsive to the angular speed of the target and to an electrical resistance proportional to said factor of proportionately for giving a tachometrical reading of the product 3. In combination with telechronographic means for predicting the distance of an aerial target and the time of flight of the projectile, graphic means for determining the product of the time of flight t and the quantity DIDZ,

a current generator responsive to the angular speed of the target, a resistance in circuit with said generator, a voltmeter in branched relation to said resistance, and means for varying the branched resistance in proportion to the quantity 22 4. In combination with telechronographic means for predicting the distance of an aerial target and the time of flight of the projectile, tachometric means responsive to the angular speed of the target, means for determining t the product of the time of flight t and the quantity including an index displaceable by the tele-' chronographic means, and means for regulating the coeflicient of proportionalityof the tachometer in accordance with the quantity 25 5. In apparatus of the character described, the combination of a time controlled movable sheet, a tracing element movable over the same to trace a graph of ranges of a moving target as a time function, a stationary surface provided with a curve adapted to indicate distances to said target in time functions of flight of the projectile, a tangent indicator movable with said element and adapted to intersect said curve to determine a point thereon the coordinates of which give directly the time of flight of the projectile and the predicted distance at the moment the projectile reaches the target, two diverging secant lines anchored at the origin of coordinates of said curve, one of which is adapted to out saidci'irve in said point, and a scale movable with said tracing element adapted to intersect the companion secant line to give readings of a fictitious time of flight for correcting the aim due to speed variations of the target.

6. In apparatus of the character described, means for tracing a graph of ranges as a time function, a stationary surface provided with a curve giving distances to the target as a function of the time of flight of the projectile, a tangent indicator to the means and adapted to intersect said second curve, a cylinder provided with fuse-setting graduatlons correspondlng to different values of the angle of sight, and a slide adapted to extend a vertical through said intersection for reading the fuse-settings.

In testimony whereof I have signed this 

